Well screen



Dec. 4, 1934. E. L. BARKER 1 WELL SCREEN Filed March 15, 1933 INVENTOR.

Patented Dec. 4, 1934 I vNlTE-DsTATEs PATENT. E

1,983,016 WELL soRE EN ErnestL. Barker, Houston 'lex ApplicationiMarch 15, 1932, sriarlno. 660,879 4foi ims. (01, let- 5) This invention relates to a wellfscreen and has more particular-relation to novel means for closing the lower end of the screen to prevent the inflow of liquid beneath into the screen. 5 In producing oil from a well a screen is set in the well opposite the oil bearing stratum to permit the inflow of the oil but to exclude sand and foreign matter. This screen is provided at its lower end, with a downwardly opening back pressure valve and when the screen is set a wash pipe is lowered through the screen and clean washing fluid is forced down through the wash pipe and out through said valve and this washing fluid passes up about the screen to wash the same. When the screen is washed clean the oil may then flow into the screen and up through the well tubing to the ground surface. It is desirable that the back pressure valve be maintained closed while the well is producing to exclude water and foreign matter from beneath. Sometimes foreign objects hold the back pressure valve open and this objectionable water and foreign matter is permitted to enter. To guard against this the invention herein described has been provided.

Another object of the invention is to provide, in a screen, a cylinder at the lower end of the screen above the back pressure valve, and a closure plug'to be dropped into said cylinder after the well has been washed, to completely close said lower end of the screen, and to maintain the same closed.

Another object is to provide a novel type of cylinder with means therein togrip and hold the plug in position and means for forming a fluid tight joint around the plug.

With the above and other objects in view this invention has particular relation to certain novel features of construction, arrangement of parts specification and illustrated in the accompanying drawing, wherein:

The drawing shows a fragmentary vertical sectional view of the lower end of the screen show- I ing the closure plug therein.

and use, an example of which is given in this annular seat 7 which is controlled by the downwardly opening back pressure valve 8. This valve is slidably mounted on the valve rod 9 whose upper end is anchored to the spider 10 and whose lower end has an enlarged head 11 thereon and around said rod and interposed between the valve 8 and head 11 there is a coil spring 12 which normally holds the valve closed.

The cylinder has a head 13 thereon which is connected to the cylinder proper by an inside coupling 14 and between the head and cylinder there is a suitable gasket 15 to form a fluid tight joint. The head 13 is approximately tubular inform and has an upwardly converging seat 16 therein terminating, at its upper end, at the annular stop 17. On this seat 16 are the upwardly tapering slips 18 which have the inside downwardly pitched teeth 19. These slips are seated on the coil spring 20 which in turn is supported on the coupling 14. The spring 20 normally holds the slips in their upper position against the stop 17.

In the upper end of the head 13 there is a tubular wash pipe seat 21 and around this seat and anchored to the head there is an upstanding tubular guide 22.

Beneath the coupling 14 and seated on an internal annular shoulder 23, in the cylinder, there is a packing assembly comprising the annular packing rings 24 and the annular spacer rings 25 arranged alternately with respect to the packing rings. The packing rings have the annular, depending, lips 26 around their inner margins which fit down within the spacer rings beneath.

When the screen is washed a cylindrical plug 2'? may be dropped through the string of pipe to the lower end of which the screen is attached. The lower end of this plug is formed with a tapered guide 28 and the plug will be guided into said cylinder and its lower end will land on the seat 29 at the lower end of the cylinder. The plug will pass between the slips 18 and its upper end has the external annular upwardly pitched teeth 30 which engage the teeth 19 and the spring 20 will hold said'slips upwardly and inwardly to maintain said teeth in such engagement and the plug The lips 26 will fit closely around the plug 27 and the entrance of fluid, from beneath, into the screen will be prevented even if the back pressure valve 8 is held open.

The drawing and description disclose what is now considered to be a preferred form of the invention by way of illustration only while the broad principle of the invention will be defined by the appended claims.

What I claim is 1. The combination with a cylinder having a converging seat therein, engaging slips on said seat, a plug fitted in the cylinder and engaged and retained therein by said slips, an annular, downwardly directed flexible lip on the cylinder wall which closely surrounds said plug, and an upwardly opening cup ring on the plug which fits closely within the cylinder. I l

2. The combination with a cylinder having an inside abutment, of a head on the cylinder, an inside coupling anchoring the head to the cylinder, annular packing between the abutment and coupling, said head having an outwardly converging seat, a slip on said seat and a spring between the coupling and slip.

3. The combination with a cylinder having an inside abutment, of a head on the cylinder, an inside coupling connecting the head to the cylinder, packing between said abutment and coupling, said packing being composed of alternately arranged packing rings and spacing rings, said packing rings having annular lips and said head having a tapering seat, engaging slips in said seat and a yieldable member between the coupling and slips.

4. The combination with a cylinder having an inside abutment, of a head on the cylinder, a packing assembly in the cylinder comprising alternately arranged packing rings and spacer rings, said packing rings having downwardly directed annular lips, an upwardly tapering slip seat in the head, slips in said seat, a plug fitted through said packing, yieldable means normally held in engagement with the plug and an upwardly directed cup ring on the plug.

ERNEST L. BARKER. 

